package thread;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * 线程池
 * 线程池是线程的管理机制，主要解决
 * 1. 线程的创建和销毁
 * 2. 线程的复用
 *
 */
public class ThreadPoolDemo {
    public static void main(String[] args) {
        //创建具有2条线程的线程池
        ExecutorService threadPool= Executors.newFixedThreadPool(3);

        for (int i = 0; i < 5; i++){
            Runnable r=new Runnable() {
                @Override
                public void run() {
                    try {
                        Thread t=Thread.currentThread();
                        System.out.println(t.getName()+"开始执行");
                        Thread.sleep(5000);
                        System.out.println(t.getName()+"执行完毕");
                    }catch (Exception e){
                        e.printStackTrace();
                    }
                }
            };
            threadPool.execute(r);
            System.out.println("将一个任务交给了线程池");

        }

        //threadPool.shutdown();
        threadPool.shutdownNow();
        System.out.println("线程池关闭");
    }
}
